less than ___ cm. ex?
1 cm. Freckels, flat nevi, hypopigmentation, petechia, measles, scarlet fever
what is this?
pustule- turbid fluid (pus) in the cavity. Circumscribed and elevated. ex) impetigo and acne
what is this?
a cyst! encapsulated fluid filled cavity in dermis or subcutaneous layer, tensely elevating the skin
what is this?
bulla.. larger than 1 cm in diameter. Usually single chambered (unilocular) superficial in epidermis; it is thin walled so it ruptures EASILY. ex) friction blister, pemphigus, burns, contact dermatitis
what is a vesicle?
Elevated cavity containing free fluid, up to 1 cm. "Blister" Clear serum flows if the wall is ruptured. ex) herpes simplex, early varicella, herpes zoster,
superficial, raised transient, erythematous, slightly irregular shape due to edema, fluid held diffusely in tissues. (ex) mosquito bite, allergic reaction.
wheals coalesce to form extensive reaction intensely pruitic
papules coalesce to form surface elevation wider than 1 cm. A plateua like disk shaped lesion. ex) psoriasis, lichen planus.
what is a papule?
something you feel. less than 1 cm. Caused by superficial thickening in the epidermis. ex: mole, lichen planus, molluscum, wart.
what is this?
gyrate, twisted, coiled, spial, snakelike.
a scratch, streak, line or stripe
or iris, resembles iris of eye, concentric rings of color in lesions
a linear arrangement along a unilateral nerve route (herpes zoster)
annular lesions grow together (lichen planus, psoriasis)
cluster of lesions ( vesicles of contact dermatitis)
what type of lesion is this?
annular or circular. Begins in center and spreads to the periphery
body's largest organ?
skin. Covers 20 square feet of surface area in the average adult. The skin is the sentry that guards the body from environmental stress (trauma, pathogens, dirt, and adapts it to other environmental influences.
skin has two layers
epidermis and the inner layer the dermis. Third layer is the subcutaneous layer of tissue.
thin but tough. The inner basal cell layer forms new skin cells. Their major ingredient is the tough fibrous protein keratin. Melanocytes are interspersed along this layer produce pigment melanin which gives brown tones to the skin and hair.
All people have same number of melanocytes. T/F
True. However, the amnt of melanin they produce varies with genetic, hormonal, and environmental influences.
From the basal layer new cells migrate up and flatten into the outer?
horny cell layer. This consists of dead keratinized cells that are interwoven and closely packed. Cells are constantly being shed, desquamatized, and replaced with new cells from below. Epidermis is completely replaced every 4 weeks. A person sheds 1 pound of skin each year!
epidermis is avascular. it is nourished by?
blood vessels in the dermis below.
Skin color is derived from three sources?
mainly from the brown pigment melanin. 2) Also from the yellow orange tones of the pigment carotene. 3) the red purple tones in the underlying vascular bed. All people have skin of varying shades of brown, yellow, and red; the relative proportion of these shades affect the prevailing color. Skin color is further modified by the thickness of skin and by the presence of edema.
inner supportive layer consisting mostly of connective tissue or collagen. Tough fibrous protein that enables skin to resist tearing. The nerves sensory receptors blood vessels and lymphatics lie in the dermis. Appendages from the epidermis such as hair follicles sebaceous glands and sweat glands are embedded in the dermis.
is adipose tissue which is made up of lobules of fat cells. The subcutaneous tissue stores fat for energy, provides insulation for temperature control, and aids in protection by its soft cushioning effect. Also the loose subcutaneous layer gives skin its increased mobility over structures underneath.
vestigual for humans; it no longer is needed for protection from cold or trauma. However, hair is higly significant in most cultures for its cosmetic and psychological meaning. Hairs are threads of keratin. Hair growth is cyclical with acting and resting phases.
Around the hair follicle is the?
muscular arrector pili which contract and elevate the hair so taht is resembles goose flesh when the skin is exposed to cold or in emotional states.
two types of hair- vellus hair?
Fine faint vellus hair covers most of the body. (except the palms and soles the dora of distal parts of fingers, umbilicus, the glans penis and inside the labia.
thicker and darker hair that grows on scalp and eyebrows, and after puberty on axillae pubic area and face and chest in male.
glands produce a protective lipid substance sebum is secreted through the hair follicles. Sebum oils lubricate skin and hair and forms an emulsion with water that retards water loss from skin. sebacious glands are everywhere except on palms and soles. They are most abundant in scalp, forehead, face, and chin.
There are two types of sweat glands
eccrine glands- coiled tubules that open directly onto the skin surface and produce a dilute saline solution called sweat. The evaporation of sweat reduces body temp. They are mature in 2 month old infant.
approcrine gland- thick milky secretion in hair follicle. Location- mainly axillae, anogenital area, nipples, and navel, and are vestigial in humans. Become active in puberty, secretion occurs with emotional and sexual stimulation.
Longitudinal ridges on nails become more prominent with?
Functions of skin
1) protection- injury, thermal, chemical, light wave sources.
2) prevent penetration- invasions of microorganisms, & prevent loss of water and electrolytes in body.
3) perception- skin sensory surface touch, pain, temp, and pressure
4) temp regulation- allow heat to dissipate through sweat glands and heat storage through subcutaneous insulation
5) identification- facial structures, hair color, finger prints
6) wound repair- skin allows cell repairment
7) absorption and secretion
8) production of vit D
Which has greatest risk for fluid loss adult or infant?
several skin conditions among blacks:
keloids, areas of hypo or hyper pigmentation, pseudofolliculitis, melasma.
scar that forms at the site of wound and grows beyond the normal boundaries of the wound
razor bumps or ingrown hairs
mask of pregnancy
aging in skin-
epidermis layer thins and flattens allowing chemicals easier access into the body. Wrinkling occurs because the underlying dermis thins and flattens. The loss of collagen increases the risk for shearing and tearing injuries
sebaceous and sweat glands- aging
decrease in function and number. Risk increases for heat stroke.
self esteem is linked to a youthful appearance. t/f
subjective data for skin, hair, nails
hair loss, change in nails, envir/occup hazards, self care behavior, excessive dryness or moisture, excessive bruising, rash, meds, change in pigmentation, change in mole size, past hx of skin disease (allergies, hives, psoriasis, eczema)
when skin breakdowns occur?
cell replacement is slower and wound healing is delayed.
use of non sterile equipment to apply tattoos increase risk of?
general change in pigmentation suggests?
systemic illness, pallor, jaudice, and cyanosis
annular lesions grow together (lichen planus, psoriasis)
turbid fluid pus in cavity. Circumscribed and elevated examples (impetigo, acne)
encapsulated fluid filled cavity in dermis or subcutaneous layer tensely elevating skin ex) sebaceous cyst, wen
larger than 1 cm diamter; usually single chambered superficial in epidermis it is thin walled so it ruptures easily. ex) friction blister pemphigus, burn, contact dermatitis
larger than a few cm in diamter firm, soft, deeper in dermis, may be deeper in dermis in the papule. ex) xanthoma, fibroma, intradermal nevi
thick dried out exudate when vesicles/ pustules burst and dry up. Color can be red brown, yellow, honey, depending on fluids ingredients (blood, serum, pus) ex) impetigo, weeping eczema, scab after abrasion
compact desiccated flakes of skin dry or greasy silvery or white from shedding of dead excess keratin cells. ex) after scarlet fever or drug reaction (laminated sheets)psoriasis, seborrheic dermatitis, eczema, ichythyosis, dry skin
linear crack with abrupt edges extends into dermis, dry, or moist. ex) cheilosis at corners of mouth due to excess moisture; athlete foot
scooped out but shallow depression. Superficial epidermis lost moist but no bleeding heals without scar because erosion does not extend in dermis
deeper depression extending in the dermis irregular shape, may bleed, leaves scar when heals. ex) stasis ulcer, pressure sore, chancre.
self inflicted abrasion superficial sometimes crusted scratches from intense itching. ex) insect bites scabies, dermatitis, varicella
after skin lesion is repaired normal tissue is lost and replaced with CT collagen. This is a permanent fibrotic change. ex) healed area of surgery or injury/acne
resulting skin level is depressed with loss of tissue, thinning of epidermis. ex) stria
prolonged intense scratching eventually thickens skin and produces tightly packed sets of papules. looks like surface of moss.
hypertrophic scar, resulting skin level is elevated by excess scar tissue. Which is invasive beyone site of original injury. May increase long after healing occurs. Looks smooth rubbery and claw like and has a higher incidence among blacks.
tiny punctate hemorrhage 1 to 3 mm round and discrete, dark red purple, or brown in color. Cause by bleeding from superficial capillaries; will not blanch. May indicate abnormal clotting factors. In dark skinned people petechiae are best visualized in areas of lighter melanization. When the skin is black or very dark brown, petechiae cannot be seen in the skin. thrombocytopenia, subacute bacterial endocarditis, and other septicemias, are characterized by petechiae in mucous membranes as well as on the skin.
purplish patch resulting from extravasation of blood into the skin > 3 mm in diameter.
confluent and extensive patch of petechiae and ecchymoses > 3 mm flat, red to purple, macular hemorrhage. Seen in generalized disorders such as thrombocytopenia and scurvy. Also occurs in old age as blood leaks from the capillaries in response to minor trauma and diffuses through dermis.
red moist maculopapular patch poor defined borders. Extend along inguinal and gluteal folds. History of infreq diaper changes or occlusive
candidasis- scalding red moist patches with sharply demarcated borders some loose scales. Usually in genital area extending along inguinal and gluteal folds. Aggravated by urine and feces. Infect superficial layers
Eczema- erythematous papules and vesicles with weeping, oozing, and crusts. Lesions usually on scalp, forehead, cheeks, forearms and wrists, elbows, back of knees. Paroxysmal and severe pruiritis. Family hx of allergies.
tinea pedis ringworm of foot
athlete foot. fungal infection. first appears as vesicles between toes sides of feet and soles and then grows scaly and hard. found in chronically warm, moist feet.
scarly erythematous patch, with silvery scales on top. Usually on scalp outside of elbows and knees, low back, and anogenital area.
inner edge of nail elevates; nail bed greater than 180 degreees. Distal phalanx looks rounder and wider. association with physiology of platelet production. Lung inflam, bronchial tumor, heart defects with R to L shunt, fragmented platelets become trapped in the fingertip vasculature, releasing platelet derived growth factor and promoting frowth of vessels which shows as clubbing. It develops SLOWLY over years. If the primary disease is treated clubbing can reverse.
basal cell carcinoma
usually starts as skin colored papule ( may be deeply pigmented with a pearly translucent top) and overlying telangiectasia (broken blood vessel) Then develops round pearly border with central red ulcer, or looks like a large open pore with central yellowing. MOST COMMON FORM OF SKIN CANCER, slow but inexorable growth. Basal cell cancers occur on sunexposed areas of face, ears, scalp, and shoulders.
squamous cell carcinoma
arise from sctinic keratoses or de novo. Erythematous scaly patch with sharp margins 1 cm or more. Develops central ulcer and surround erythema. Usually on hands/head exposed to UV radiation. Less common than basal cell carcinoma but grows rapidly
serious arthritis cardiac or neuro sequalia. Caused by spirochete bacterium carried by black or dark brown deer tick. 1st stage has distinctive bull eye, red macular or papular rash, in 50% of cases. The rash radiates from site with some central clearing and is usually located in axillae, middriff, inguina, or behind knees, with regional lymphadenopathy. Rash fades in 4 weeks. untreated individuals may have disseminated disease with fatigue, anorexia, fever, chills, joint or muscle aches. Antibiotics are tx.
herpes simplex virus
infection has prodrome of skin tingling and sensitivity. Lesion then erupts with tight vesicles followed by pustules and then produces acute gingivostomatitis with many shallow painful ulcers. Common location is upper lip, oral mucosa, tongue.
Aids related Kaposi Sarcoma
patch stage, vascular tumor and is the most common tummor in HIV person. Can occur at any stage in HIV. Can be easily mistaken for bruise or nevi
scalp ringworm tinea capitis
patchy rounded hair loss on scalp. leave broken off hairs pustules and scales on skin. Caused by fungal infections leasions may fluoresce blue green under woods light. Commonly seen in children and farmers. Contagious.